Low surface energy and a low kinetic coefficient of friction are desirable properties for certain polymeric materials. Fluoropolymers possess several highly useful material properties, including low surface energy, low chemical reactivity and low kinetic coefficient of friction (high lubricity). However, fluoropolymers are more expensive and more difficult to process than most other polymer-based materials. Simply overcoating less costly polymers with fluoropolymers is often impractical because of the high temperatures involved in the processing of the fluoropolymers and/or the poor adhesion of fluoropolymers to most other materials.
The requirements for an elastomeric material with high thermal stability are satisfied, for example, by silicone rubber. However, when utilized in photocopier rolls, this material shows undesirably high levels of retention of toner when functioning in duplex (double-sided) mode.
Modification of certain polymers to induce desirable properties is described in Ning et al., Polym. Bull. (Berlin) 1984, 12, 407-11 and in Mauritz et al., 1989, ACS Symp. Ser. 395 (Multiphase Polym.: Blends Ionomers), 401, wherein silica is deposited inside swollen polymers, and in U.S. Pat. No. 5,252,654 issued Oct. 12, 1993, which describes a polymeric composite of an organic polymer and an inorganic glassy polymer and a process for making such composites which are useful as protective coatings.